Agricultural Tractor’s Tire Resistance Due to the Deflection and It’s Influence on Traction on Agricultural Soils

Abstract

The paper discusses in what degree the usage of agricultural tractor tires with lower rolling resistance can benefit in traction. The component of the rolling resistance due to deflection that depends on tire design characteristics and that considerably easy can be measured is analyzed. The resistance of tires due to the deflection and footprint characteristics for tires 12.4R28 made by different manufacturers was determined experimentally. Using numerical traction model, influence of measured values on the tractor’s tractive performance was analyzed. Obtained results show significant difference of deflection resistance for tested tires and imply that tire selection for agricultural tractors, among other criterions, may be based on sellection of tires with lower rolling resistance and longer footprint. For two tested tires obtained difference for tractive efficiency was about 4 % for tilled and soft soils.

U radu se utvrđuje u kolikoj meri korišćenje pogonskih pneumatika poljoprivrednog traktora sa manjim otporima kotrljanja može da dovede do poboljšanja pokazatelja vuče. Prvenstveno se razmatra defleksioni otpor, komponenta otpora kotrljanja koja je direktno uslovljena konstrukcijom pneumatika, a koju je relativno lako izmeriti. Eksperimentalnim putem su određeni defleksioni otpori i karakteristike kontaktne površine dva pneumatika 12.4R28 različitih proizvođača, te numeričkom analizom utvrđen njihov uticaj na pokazatelje vuče traktora. Dobijeni rezultati su ukazali na značajne razlike ovih otpora, te da se kao jedan od upotrebljivih kriterijuma za izbor pogonskih pneumatika poljoprivrednih traktora može primeniti i izbor onih sa manjim defleksionim otporima i dužom kontaktnom površinom. Za ispitivane pneumatike utvrđena je razlika u efikasnosti vuče od oko 4 % na uzoranim i mekim podlogama.